Zahid Mubarek was murdered by Robert Stewart in 2000 at Feltham young offenders' institution. An inquiry identified 186 failings in the prison system. Photograph: Rex Features

There is a serious danger that a murder like that of a young British Asian man, Zahid Mubarek, by his violent racist cellmate 14 years ago could happen again, the chief inspector of prisons has warned.

Nick Hardwick says that despite positive changes in prisons since the murder, the drive for reform has been weakened or forgotten.

Mubarek, 19, was murdered in Feltham young offenders' institution in March 2000 by Robert Stewart, a known violent racist with mental health problems who had bragged about committing the first murder of the millennium.

A judicial inquiry was only held into Mubarek's death after the House of Lords ordered it following a four-year campaign by his family. The inquiry, chaired by Mr Justice Keith, identified 186 failings in the prison system, describing it as "institutionally racist". The murder has been described as the prison service's "Stephen Lawrence moment".

Hardwick's assessment, published on Tuesday, says Mubarek's death was preventable and there are now better systems in place to make it less likely that a violent racist could be placed in a cell with a vulnerable prisoner. A list of violent racists serving sentences in England and Wales is believed to have 75 names on it.

"However, it could happen again," said Hardwick. "Risk assessment procedures are often delayed or poorly completed and information sharing is still a considerable weakness across the prison estate. Too many prisoners still share cells designed for one regardless of sentence status, age or other issues of compatibility. Prisoners from black and ethnic minority groups consistently report a worse experience than white prisoners."

Hardwick added that while the national offender management service had said it fully implemented most of the inquiry's recommendations, they were no longer being given enough priority when decisions were made about to use the prison service's diminished resources.

Mubarek's uncle Imitiaz Amin said the new report showed the authorities had failed to make a long-term impact. He added that he hoped the report provided a catalyst for further action given that violence and deaths remained alarmingly high in prisons in England and Wales.

The latest figures show that more than 20,000 prisoners are "doubled up". While inmate-on-inmate assaults have fallen for young offenders by 2,500 incidents a year, they are up by 1,500 a year for adult male prisoners.

Four prisoners were murdered inside jails in England and Wales last year but this was unusual. There were 26 murders in the decade before the introduction of a cell-sharing risk assessment in 2000, since when there has been 20 homicides in 13 years.

Amin, who is also chief executive of the Zahid Mubarek Trust, which works inside 10 prisons across London, said: "Discrimination and equality work is no longer on the agenda. It is deeply worrying that where the implementation has succeeded in satisfying tick boxes, the authorities have failed to achieve the long-term impact to address the areas of concern described by the Zahid Mubarek inquiry. We hope this report provides the catalyst for further action."